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Growatt spf5000es with JK BMS

Hermanvanveen

New Member
Joined
Sep 22, 2021
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19
Hello,

- growatt spf5000es
- JK 16S 200ah BMS
- 16x 304 eve cells

I wonder if my assumptions are correct:

- bms detect a cell voltage is too low:
Growatt unit shuts down completely. Charging has to be done with an external charger

- bms detect a cell voltage is too high:
Growatt unit stays on, gives no errors, but no solar energy will be put through the bms towards the battery

Is this correct?

Thank you
 
Hello,

- growatt spf5000es
- JK 16S 200ah BMS
- 16x 304 eve cells

I wonder if my assumptions are correct:

- bms detect a cell voltage is too low:
Growatt unit shuts down completely. Charging has to be done with an external charger

- bms detect a cell voltage is too high:
Growatt unit stays on, gives no errors, but no solar energy will be put through the bms towards the battery

Is this correct?

Thank you

The answer is maybe.... and that is final!

It all depends on the BMS and how the system is set up.
  • Typically, the growatt will be set up to shut down discharge at a voltage that is slightly higher than the BMS would trigger a low voltage disconnect.
  • Typically, the growatt will be set up to stop charging at a voltage that is slightly lower than the BMS would trigger a low voltage disconnect.

So.... typically the BMS never does either a high voltage disconnect or a low voltage disconnect.
If something fails and the BMS does a disconnect, what happens next depends on the BMS
  • Most modern BMSs will still allow charging after a low voltage disconnect. Once the growatt charges the batteries back to a 'recovery' voltage, the BMS returns to normal operation.
  • Most modern BMSs will still allow discharge after a high voltage disconnect. Once the growatt drains the batteris back down to a 'recovery' voltage the BMS returns to normal operation.
However, Some BMSs are designed to require manual intervention to restart. The theory being that if something went wrong, then it needs to be investigated before the system is allowed to go back to normal operation.
 
  • Most modern BMSs will still allow charging after a low voltage disconnect. Once the growatt charges the batteries back to a 'recovery' voltage, the BMS returns to normal operation.

In contrast with other systems, the growatt is an "all in one unit". Charge controller, inverter and ac charger. For it to charge the battery after the bms had a low cell disconnect, it needs to be on (and thus consumes electricity). In contrast to seperate charge controllers. So tgat made me thinking that the bms shuts down tge growatt completely (since it consumes about 50 watt), which tgen makes charging using the growatt impossible.
  • Most modern BMSs will still allow discharge after a high voltage disconnect. Once the growatt drains the batteris back down to a 'recovery' voltage the BMS returns to normal operation.

Clear, thanks
 
I nearly have the exact setup, I have just fitted the JK bms (Yesterday) so cant yet comment on its performace and still learning myself, but i would presume if you setup up the Growatt to control the overcharge and undercharge then the only time the jk bms would come into play other than balancing, is if it, either has a low cell reading or the growatt fails in which case you would want this. If one cell cant keep up with the others I would want it to shut down so I could investigate the problem. As, I have said im new to this so any comments would be appreciated
 
How did you connect JK-BMS to Growatt? Via RS485 port? Any special settings required?
 
How did you connect JK-BMS to Growatt? Via RS485 port? Any special settings required?
I personally don't see a need for a coms port connection between the BMS and the Growatt.
- Set the growatt with the charge cut-off and discharge cut-off voltages that you normally want to run your batteries at
- Set the JK BMS High voltage disconnect slightly higher than the charge cut-off the Growatt is set for
- Set the JK BMS low voltage disconnect values slightly lower than the discharge cut-off the Growatt is set for
*Done* There are two levels of protection of the cells and No coms port is needed.
 
I personally don't see a need for a coms port connection between the BMS and the Growatt.
- Set the growatt with the charge cut-off and discharge cut-off voltages that you normally want to run your batteries at
- Set the JK BMS High voltage disconnect slightly higher than the charge cut-off the Growatt is set for
- Set the JK BMS low voltage disconnect values slightly lower than the discharge cut-off the Growatt is set for
*Done* There are two levels of protection of the cells and No coms port is needed.
Yes, maybe it is the best and the simplest way to provide protection. Do you use USE or US2 battery mode? I tried US2 and LI icon is blinking(no connection) and then also the charging is not working as it should. So I set it at USE for now(Still waiting for BMS).
 
I nearly have the exact setup, I have just fitted the JK bms (Yesterday) so cant yet comment on its performace and still learning myself, but i would presume if you setup up the Growatt to control the overcharge and undercharge then the only time the jk bms would come into play other than balancing, is if it, either has a low cell reading or the growatt fails in which case you would want this. If one cell cant keep up with the others I would want it to shut down so I could investigate the problem. As, I have said im new to this so any comments would be appreciated
Any updates and further results ?
thx
 
Things will become simpler. Contact the growat factory to obtain their communication protocol. According to this communication protocol, a fully communicating jkbms is being customized, which will produce a new model,
When there is the latest news, I will reply in this post, which should be in this month
Hello,

- growatt spf5000es
- JK 16S 200ah BMS
- 16x 304 eve cells

I wonder if my assumptions are correct:

- bms detect a cell voltage is too low:
Growatt unit shuts down completely. Charging has to be done with an external charger

- bms detect a cell voltage is too high:
Growatt unit stays on, gives no errors, but no solar energy will be put through the bms towards the battery

Is this correct?

Thank you
 
Things will become simpler. Contact the growat factory to obtain their communication protocol. According to this communication protocol, a fully communicating jkbms is being customized, which will produce a new model,
When there is the latest news, I will reply in this post, which should be in this month
Hi,

I have a similiar issue but with the Growatt SPH4600 single phase inverter and a JK BMS I got from banggood that arrived today.
I had purchased the canbus one but it looks like that the B2A24S20P is not ready for use with Growatt SPH 4600.
It is a shame cause I had asked them before cause I had known how the SEPLOS is working smoothly just by selecting the growatt brand and the right protocoll iin their PC software, but they could not balance that much so I decided to follow Andy from the channel Off Grid Garage in australia who had reommanded jk bms a lot in his videos most recently but not touching the canbus topic which I have to sort out in advance before my 16 cells from EVE with 173 Ah will arrive.

I simply wanna get JK running with the growatt cause no one had done a documentation for that and there is a huge demand in central europe for that cause otherwise I have to buy a SEMPLOS BMS which can do the job by simply changing the setup in the software by changing the protocoll to CAN and Growatt. I had seen the video on the SEPLOS Alibaba shop that showed that also deye and a lot others.

And if we have to obtain the protocoll from Growatt then you know the outcome:
Growatt does not release anything to let competition into their core business selling batteries

How stupid should they be to do that. So the outcome is obvious or you simply do the job that SEPLOS had done to and mineals or so too.
Reverse engineering or lending units in china to reverse engineer that.

thx
 
Last edited:
Things will become simpler. Contact the growat factory to obtain their communication protocol. According to this communication protocol, a fully communicating jkbms is being customized, which will produce a new model,
When there is the latest news, I will reply in this post, which should be in this month
is there any new model for communicating with growatt 5000ES ?

also i wold like to know is there any way to parallel the jkbms (i have 2 packs 150 ah 16s and 100ah 16s )
 
is there any new model for communicating with growatt 5000ES ?

also i wold like to know is there any way to parallel the jkbms (i have 2 packs 150 ah 16s and 100ah 16s )
afaik the only real BMS working with the growatt lineup via canbus are the SEPLOS BMS which now has gotten BT and App Support too.
But usually the SEPLOS BMS fully integrates into the Growatt Shine Wifi App via SEPLOS BMS, but the BT App support makes it easier to configure the battery if you need.
Otherwise SEPLOS are usually running with a windows only software which means you would need a PC to connect to the BMS and make changes.

Best spot to source is Aliexpres and there a shop called MINERALS which also calls it minerals.
I got my second batch from Aliexpress shop minerals and could check the hardware with the SEPLOS I had gotten from the Seplos shop.

Why ?
Cause SEPLOS sucks regarding shipping and customs and shipping services. I had to pay customs and VAT twice, so I ended up to pay 50€ = $ on top even though I had paid at checkout the VAT for the EU.

I do not know any other CANBUS BMS that is supporting Growatt. Be aware that you might have to change the CANBUS dialect cause Growatt has 2 dialects , 1 for SPH and 1 for ES / EPS off grid series. YOu need to choose the right dialect once your laptop is connected to the BMS.

JK is dead regarding CAN BUS - they had claimed to support CAN BUS and Growatt but they meant to say that they are adding the chip and you have to get the Canbus protocol and its definition from Growatt, which obviously Growatt rejected. This meant that i had to sell the JK BMS and switch to SEPLOS. JK support was unwilling to help and blamed the customer cause they will tell you that it is your job to obtain / get the growatt canbus from Growatt. sad but true
 
afaik the only real BMS working with the growatt lineup via canbus are the SEPLOS BMS which now has gotten BT and App Support too.
But usually the SEPLOS BMS fully integrates into the Growatt Shine Wifi App via SEPLOS BMS, but the BT App support makes it easier to configure the battery if you need.
Otherwise SEPLOS are usually running with a windows only software which means you would need a PC to connect to the BMS and make changes.

Best spot to source is Aliexpres and there a shop called MINERALS which also calls it minerals.
I got my second batch from Aliexpress shop minerals and could check the hardware with the SEPLOS I had gotten from the Seplos shop.

Why ?
Cause SEPLOS sucks regarding shipping and customs and shipping services. I had to pay customs and VAT twice, so I ended up to pay 50€ = $ on top even though I had paid at checkout the VAT for the EU.

I do not know any other CANBUS BMS that is supporting Growatt. Be aware that you might have to change the CANBUS dialect cause Growatt has 2 dialects , 1 for SPH and 1 for ES / EPS off grid series. YOu need to choose the right dialect once your laptop is connected to the BMS.

JK is dead regarding CAN BUS - they had claimed to support CAN BUS and Growatt but they meant to say that they are adding the chip and you have to get the Canbus protocol and its definition from Growatt, which obviously Growatt rejected. This meant that i had to sell the JK BMS and switch to SEPLOS. JK support was unwilling to help and blamed the customer cause they will tell you that it is your job to obtain / get the growatt canbus from Growatt. sad but true
oops . thank you for update. I chose JK because of its active balancing feature . is SEPLOS has this feature too ?
 
oops . thank you for update. I chose JK because of its active balancing feature . is SEPLOS has this feature too ?
guess what: i had the same thoughts like you 9 months ago and was happy to get the JK canbus from banggood or so till I got the full picture that it is not working that way.

SEPLOS BMS Balancer is there and it seems to be working cause a german youtuber had done some investigations and release a video how it is performing among his 100 kWh big battery . He has added a 15 kWh Seplos powered battery from such kit, you know those whole kits incl .metal case , special bus bars and so on.

One chapter or 2 had been about the topic of balancing and the improvement achieved meanwhile by Seplos cause SEPLOS is the only BMS which firmware can be updated too and that becomes important in such cases of improvements and bug fixing. Big plus over JK.

My cells are currently in the 30 day rest and I will get results from the BMS not before February.

But I can also tell you that there had been some issues described in videos from another german youtuber but he has emigrated to australia and therefore his content is english too therefore check the channel off-grid garage
He is a strong force working with suppliers that had first failed and then over time improved. One example you can check also on his channel is the Neey Balancer. Finally in the 4th edition andy was surprised how good that had become.

Yes, it is a dedicated Balancer of 5A or so and another 100$ but it is my fall back solution if things would go wrong and I would need it. This means all my cells are connected with small wires to a small din rail 1 to 2 connector , which means 1 cable to the cell only and 2 options to connect from that cable to different units like the BMS and a Balancer. This way you can easily exchange one or the other instead of heaving to deal with 32 cables inside the battery box.

BUT: remember that Andy had found the issues of the SEPLOS first as for the Neey active Balancer Version 2 and 3 till he got the 4 working as he had told them. Then Andy added the Neey but only a few times a year so every 2 or 3 months to equalize the cells cause the former SEPLOS had the issue.

Then the SEPLOS firmware arrived and had been checked by the german youtuber who had updated the BMS first and then started his observations of the balancing. He was quite happy and reported about the progress he had found over the issues Andy had faced before in Australia.
Unfortunatelly Andy has not yet gettin back to the old SEPLOS BMS and upgraded and checked the balancer again or I might have missed that. Not sure, but I appreciate both channels cause they follow german precision and love for details so I trust and rely on their experience in my purchase decision. Why ? Cause Andy is riding ahead and willing to support people and community if things do not work out as he had seen.

Off-grid garage offers a ton of content and an awfull lot of experiments, things doing differently and questioning the status quo for example the question of heat along the busbar chain and causes and countermeasures. QUite long videos but you will learn a lot of these cause I had taken a 1 month break to watch all of Andy's videos and achievement like the connection / connector bar between cells and bms / balancer described above.

JK is what it is but I would not believe in their customer support while Seplos support is helpfull as Andy has mentioned in his videos.
If you want a growatt integration of a diy battery then there is currently no way around the SEPLOS aka minerals from AliExpress in my opinion except you wanna buy a ready to use 5 or 10 kWh battery which had been our first choice till we realized that the vendors are lying about the heritage of their cells, the quality, capactiy and what not or / and steadily increasing prices on alibaba cause each day they had found a new fee you should have to pay or if you wanted to order they simply replied: you can not order HomeStorage A anymore cause we now have a new successor called A1 and A1 is 1250$ (which meant just 250$ more even though everything had been the same spec wise except the case).

I will add a link in my next post cause I am not aware about the rules and do not wanna seen this post being deleted for adding a link.
Just 2 minutes and you will find the link.
 
oops . thank you for update. I chose JK because of its active balancing feature . is SEPLOS has this feature too ?
here is the link to one of the SEPLOS like ( i mean you can call them relabeled twins)

At the end it is a bet but this is the best choice for me right now if you want a full integration of the battery into the Growatt App and Cloud solution cause that is what I need to support my dad remotely. He can not hook up a Windows PC or Laptop to the BMS (via USB cable & converter) to look and check.

But be aware that SEPLOS has released a brand new version of the BMS which Andy had been investigating already. And guess what: a few days later the Minerals shop has also a new BMS with the same changes like a new LCD you can buy on top . This one then comes with a BT connection so people had been thinking to get the new LCD and with that the BT and App Support. This did not work out for the old V16 BMS like I had gotten.
This means check the different offers and each time you read about App or BT support (which requires the display) you can be sure that this is the newest SEPLOS BMS.

Of cause not easy or quite complex but it will end in a way that your Growatt system will identiy the diy battery as it had been a growatt battery from the growatt factory. If this is your goal then the SEPLOS BMS sold by Minerals official whatever store is the right and easiest choice at least for inside EU cause SEPLOS had caused a lot of pain and customs and fees that I was able to avoid with the Minerals order via AliExpress. And again: do not buy the SEPLOS BMS from their own website cause you might face the same issues I had faced, so no purchase on alibaba nor the seplos manufacturer website, AliExpress was faster and a lot cheaper.
 
here is the link to one of the SEPLOS like ( i mean you can call them relabeled twins)

At the end it is a bet but this is the best choice for me right now if you want a full integration of the battery into the Growatt App and Cloud solution cause that is what I need to support my dad remotely. He can not hook up a Windows PC or Laptop to the BMS (via USB cable & converter) to look and check.

But be aware that SEPLOS has released a brand new version of the BMS which Andy had been investigating already. And guess what: a few days later the Minerals shop has also a new BMS with the same changes like a new LCD you can buy on top . This one then comes with a BT connection so people had been thinking to get the new LCD and with that the BT and App Support. This did not work out for the old V16 BMS like I had gotten.
This means check the different offers and each time you read about App or BT support (which requires the display) you can be sure that this is the newest SEPLOS BMS.

Of cause not easy or quite complex but it will end in a way that your Growatt system will identiy the diy battery as it had been a growatt battery from the growatt factory. If this is your goal then the SEPLOS BMS sold by Minerals official whatever store is the right and easiest choice at least for inside EU cause SEPLOS had caused a lot of pain and customs and fees that I was able to avoid with the Minerals order via AliExpress. And again: do not buy the SEPLOS BMS from their own website cause you might face the same issues I had faced, so no purchase on alibaba nor the seplos manufacturer website, AliExpress was faster and a lot cheaper.
Hey @WOLF-GANG, is there a version you can link to for 24v nominal lifepo4 (29.2v, 8s configuration) with 200a charge/discharge?
 
INVERTER BMS IS AVAILABLE
Hi Nami.

Could you be more explicit on what is available?
A solution to get JK active balancing BMS to communicate with Growatt (SPH3-6K) inverter at last?..

Thanks.
 
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